From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-dev-return-2458-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [66.179.20.138]) by lists.oasis-open.org (Postfix) with ESMTP id 09CF158190FC for ; Mon, 7 Aug 2017 23:10:14 -0700 (PDT) Message-ID: <59895668.9090104@intel.com> Date: Tue, 08 Aug 2017 14:12:56 +0800 From: Wei Wang MIME-Version: 1.0 References: <1501742299-4369-1-git-send-email-wei.w.wang@intel.com> <1501742299-4369-5-git-send-email-wei.w.wang@intel.com> <20170803091151.GF12521@dhcp22.suse.cz> In-Reply-To: <20170803091151.GF12521@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: [virtio-dev] Re: [PATCH v13 4/5] mm: support reporting free page blocks To: Michal Hocko Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, mst@redhat.com, mawilcox@microsoft.com, akpm@linux-foundation.org, virtio-dev@lists.oasis-open.org, david@redhat.com, cornelia.huck@de.ibm.com, mgorman@techsingularity.net, aarcange@redhat.com, amit.shah@redhat.com, pbonzini@redhat.com, liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu@aliyun.com List-ID: On 08/03/2017 05:11 PM, Michal Hocko wrote: > On Thu 03-08-17 14:38:18, Wei Wang wrote: > This is just too ugly and wrong actually. Never provide struct page > pointers outside of the zone->lock. What I've had in mind was to simply > walk free lists of the suitable order and call the callback for each one. > Something as simple as > > for (i = 0; i < MAX_NR_ZONES; i++) { > struct zone *zone = &pgdat->node_zones[i]; > > if (!populated_zone(zone)) > continue; Can we directly use for_each_populated_zone(zone) here? > spin_lock_irqsave(&zone->lock, flags); > for (order = min_order; order < MAX_ORDER; ++order) { This appears to be covered by for_each_migratetype_order(order, mt) below. > struct free_area *free_area = &zone->free_area[order]; > enum migratetype mt; > struct page *page; > > if (!free_area->nr_pages) > continue; > > for_each_migratetype_order(order, mt) { > list_for_each_entry(page, > &free_area->free_list[mt], lru) { > > pfn = page_to_pfn(page); > visit(opaque2, prn, 1< } > } > } > > spin_unlock_irqrestore(&zone->lock, flags); > } > > [...] > What do you think if we further simply the above implementation like this: for_each_populated_zone(zone) { for_each_migratetype_order_decend(1, order, mt) { spin_lock_irqsave(&zone->lock, flags); list_for_each_entry(page, &zone->free_area[order].free_list[mt], lru) { pfn = page_to_pfn(page); visit(opaque1, pfn, 1 << order); } spin_unlock_irqrestore(&zone->lock, flags); } } Best, Wei --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Wang Subject: Re: [PATCH v13 4/5] mm: support reporting free page blocks Date: Tue, 08 Aug 2017 14:12:56 +0800 Message-ID: <59895668.9090104@intel.com> References: <1501742299-4369-1-git-send-email-wei.w.wang@intel.com> <1501742299-4369-5-git-send-email-wei.w.wang@intel.com> <20170803091151.GF12521@dhcp22.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, mst@redhat.com, mawilcox@microsoft.com, akpm@linux-foundation.org, virtio-dev@lists.oasis-open.org, david@redhat.com, cornelia.huck@de.ibm.com, mgorman@techsingularity.net, aarcange@redhat.com, amit.shah@redhat.com, pbonzini@redhat.com, liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu@aliyun.com To: Michal Hocko Return-path: Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: In-Reply-To: <20170803091151.GF12521@dhcp22.suse.cz> List-Id: kvm.vger.kernel.org On 08/03/2017 05:11 PM, Michal Hocko wrote: > On Thu 03-08-17 14:38:18, Wei Wang wrote: > This is just too ugly and wrong actually. Never provide struct page > pointers outside of the zone->lock. What I've had in mind was to simply > walk free lists of the suitable order and call the callback for each one. > Something as simple as > > for (i = 0; i < MAX_NR_ZONES; i++) { > struct zone *zone = &pgdat->node_zones[i]; > > if (!populated_zone(zone)) > continue; Can we directly use for_each_populated_zone(zone) here? > spin_lock_irqsave(&zone->lock, flags); > for (order = min_order; order < MAX_ORDER; ++order) { This appears to be covered by for_each_migratetype_order(order, mt) below. > struct free_area *free_area = &zone->free_area[order]; > enum migratetype mt; > struct page *page; > > if (!free_area->nr_pages) > continue; > > for_each_migratetype_order(order, mt) { > list_for_each_entry(page, > &free_area->free_list[mt], lru) { > > pfn = page_to_pfn(page); > visit(opaque2, prn, 1< } > } > } > > spin_unlock_irqrestore(&zone->lock, flags); > } > > [...] > What do you think if we further simply the above implementation like this: for_each_populated_zone(zone) { for_each_migratetype_order_decend(1, order, mt) { spin_lock_irqsave(&zone->lock, flags); list_for_each_entry(page, &zone->free_area[order].free_list[mt], lru) { pfn = page_to_pfn(page); visit(opaque1, pfn, 1 << order); } spin_unlock_irqrestore(&zone->lock, flags); } } Best, Wei From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id 723BB6B025F for ; Tue, 8 Aug 2017 02:10:13 -0400 (EDT) Received: by mail-pf0-f197.google.com with SMTP id g9so23909505pfk.13 for ; Mon, 07 Aug 2017 23:10:13 -0700 (PDT) Received: from mga01.intel.com (mga01.intel.com. [192.55.52.88]) by mx.google.com with ESMTPS id 71si409740pfy.79.2017.08.07.23.10.12 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 07 Aug 2017 23:10:12 -0700 (PDT) Message-ID: <59895668.9090104@intel.com> Date: Tue, 08 Aug 2017 14:12:56 +0800 From: Wei Wang MIME-Version: 1.0 Subject: Re: [PATCH v13 4/5] mm: support reporting free page blocks References: <1501742299-4369-1-git-send-email-wei.w.wang@intel.com> <1501742299-4369-5-git-send-email-wei.w.wang@intel.com> <20170803091151.GF12521@dhcp22.suse.cz> In-Reply-To: <20170803091151.GF12521@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, mst@redhat.com, mawilcox@microsoft.com, akpm@linux-foundation.org, virtio-dev@lists.oasis-open.org, david@redhat.com, cornelia.huck@de.ibm.com, mgorman@techsingularity.net, aarcange@redhat.com, amit.shah@redhat.com, pbonzini@redhat.com, liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu@aliyun.com On 08/03/2017 05:11 PM, Michal Hocko wrote: > On Thu 03-08-17 14:38:18, Wei Wang wrote: > This is just too ugly and wrong actually. Never provide struct page > pointers outside of the zone->lock. What I've had in mind was to simply > walk free lists of the suitable order and call the callback for each one. > Something as simple as > > for (i = 0; i < MAX_NR_ZONES; i++) { > struct zone *zone = &pgdat->node_zones[i]; > > if (!populated_zone(zone)) > continue; Can we directly use for_each_populated_zone(zone) here? > spin_lock_irqsave(&zone->lock, flags); > for (order = min_order; order < MAX_ORDER; ++order) { This appears to be covered by for_each_migratetype_order(order, mt) below. > struct free_area *free_area = &zone->free_area[order]; > enum migratetype mt; > struct page *page; > > if (!free_area->nr_pages) > continue; > > for_each_migratetype_order(order, mt) { > list_for_each_entry(page, > &free_area->free_list[mt], lru) { > > pfn = page_to_pfn(page); > visit(opaque2, prn, 1< } > } > } > > spin_unlock_irqrestore(&zone->lock, flags); > } > > [...] > What do you think if we further simply the above implementation like this: for_each_populated_zone(zone) { for_each_migratetype_order_decend(1, order, mt) { spin_lock_irqsave(&zone->lock, flags); list_for_each_entry(page, &zone->free_area[order].free_list[mt], lru) { pfn = page_to_pfn(page); visit(opaque1, pfn, 1 << order); } spin_unlock_irqrestore(&zone->lock, flags); } } Best, Wei -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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